Field
Exemplary embodiments relate to a liquid crystal display device and a method of manufacturing the liquid crystal display device.
Discussion of the Background
A liquid crystal display (LCD) device, which is one of the most widely-used display devices, includes two substrates on which field-generating electrodes such as pixel electrodes and a common electrode are formed and a liquid crystal layer which is disposed between the two substrates.
The LCD device generates an electric field by applying a voltage to the field-generating electrodes and determines an alignment direction of liquid crystals in the liquid crystal layer. The LCD device displays an image by controlling the polarization of light incident thereupon.
The liquid crystals in the liquid crystal layer need to be aligned in a particular direction at the interfaces between the liquid crystals and the field-generating electrodes to realize an image. The uniformity of the alignment of the liquid crystals is one of the most important factors that determine the display quality of the LCD device. Accordingly, one or more alignment layers having anisotropy are disposed between the liquid crystal layer and the field-generating electrodes so as to make an initial arrangement state and the alignment direction of the liquid crystals uniform.
An alignment layer having anisotropy may be formed by applying light to a polyimide (PI)-based alignment layer including a polymer having a photo-reactive group and an imide group in the repeating unit of a main chain thereof so as to impart anisotropy to the PI-based alignment layer. The alignment layer may become anisotropic through photo-isomerization or photo-decomposition caused by the irradiation of polarized light.
It is noted, however, there is a limit in improving the display quality of an LCD device using a PI-based alignment layer including a polymer having a photo-reactive group. For example, a PI-based alignment layer including a photo-reactive group has low thermal stability and low hardness, and thus, may cause various problems such as alignment instability and image sticking due to a weak alignment force.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.